Pump-plunger



R. E. CARMICHAEL.

PUMP PLUNGER. APPLICATION FILEDJULY 15,1920.

Patented Nov. s, 1921.

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UNITED NsTAiTi-:s

ROBERT' E. cautionner., `or HoUs'roN, TEXAS.

PUMP-PLUNGER. p

Speciication of Letters Patent.

Patented Nov. 8, 1921.

Application iiled1 July 15, 1920. Serial No. 396,517.`

mixed with quantitiesotsand or grit tend ing to wear the plunger. An object of my invention is to provide plunger having automatically expanding means thereon which will, by expanding, take up the wear caused by working ot the peump, and hence maintain a tight contact tween the plunger and working barrel for y long periods of time.

Another ob]ect is to provide a plunger `which will be automatically ada table to take up wear and which will also e simple in structure, easy to repair and economical to manufacture.

Referring to the drawing forming apart `of :this specification, and wherein like numerals of reference are applied to like parts throughout the several views; Figure 1 is a central` longitudinal section through a pum barrel and my improved plunger Fig. 2 is a central longitudinal-sec# tion through my improved expanding cup, and Fig. 3 1s a top plan view thereof.

I have shown 1n `ex andingmeans asused upon a plunger` o or inary construction at- .i tached at the lower end of a hollow pump 40 rod 1, and working within a pump barrel 2. The body of the plunger comprises a central tubular member 3 attached by means of a coupling 4 to the pump rod 1. At the point of connection between the pump rod and the plunger 3, I have attached a valve seat 5 of "ordinary, construction, within which an upwardly opening ball valve 6 is seated.

My expanding means comprises a cup 7 slidably mounted upon the outer face of the plunger 3. This expanding1 cup is preferably made u of some tou lexible material, Such as lliard rubber, abbitt metal, or some composition which ma be moved outwardly against the wall of t 1e working barrel. The cup is somewhat truste-conical in# shape, having the larger end placed upwardly upon the plunger and having the ulpper face beveled inwardly at 8 to apoint c osely adjacent the plunger, where it is beveled inwardly at a sharp angle. The mner face of the cup isvcylindrica] in shape and has a kerf or groove 9 cut therein for a distance of approximately halt' way through the material at that point. Thesaid kerf a1- lows the upper part of the cup to bend out wa-rdly, the kerf opening up as the move# ment outwardly proceeds. By this provision non-resilient materials, such as lead,

may be used in making the cup. The cup is also divided longitudinally into a plurality of parts; In 3 I have shown the cup as thus divided into four sections, the division line l() ofthese sections being cut approximately tangentlto the inner face of the cup. This, aswill be noted, will allow an outward expansion of the longitudinal sections of the cup and will maintain a tight.`

contact between the sections.

- In securing this cup in position upon the plunger I use a cup Shaped washer 11, ol such sizeand shape as to closely fit about the lower end of the cup 7 and to extend upwardly on the outer surface thereof to a point somewhat abovelthe inner kerf 9. The cup and the washer are secured upon the plunger by means of locking nuts 12 and 13 threaded upon the lower end of the part 3.

`Above the cup 7 I provide a slidable conical collar 14. The smaller end of this collar is pointed downward and is adapted to fit within the beveled upper face of the cup 7 This collar 14 serves as an expanding member and is adapted when forced downwardly within the beveled upper end of the cup 7 to force the sections thereof outwardly into Contact with the working barrel.

The means by which the collar 14 is forced downwardly comprises a spiral spring 15 surrounding the tubular plunger 3, and bearingat its upper end upon a nut 16 threaded upon the outer face of the plunger below the coupling member 4. The spring 15 bears at its lower end upon a washer 17 seated upon the upper face of the collar 14. The washer 17 1s threaded on its outer` face for attachment to a tubular housing 18, which extends upwardly about the spring and the coupling 4 and has an inwardly projecting fiange 19 at its upper end fitting closely i mg about the pump rod l. A slidable but fluid tight t is maintained between the housing and the pump rod 1, by means of a stuiling box 20 `of ordinary construction;

The operation of my device will now be apparent. When the plunger is reciprocating within the working barrel the upper outer point 2l upon the cup 7' will bear tightly against the inner face ofthe working barrel and thereby maintain the necessary suctionto cause the customary operation of the plunger. Sand and grit which may be carriedin suspension `within the liquid bepumped will be scraped away from the face-of the working barrel and will not be allowed'passage upwardly outside the cup. Wear will be caused, however, upon the edge 2l' andthe spring l5` will serve to force the ,collar downwardly, and thus act to exert a` constant pressure outwardly against the cup 7 causing it to automatically expand during voperation and ltake up any wear whichm'ay occur. As the cup 7 is gradually expanded it will causey the upper end thereof to be ,forced outwardly opening the cupv at fthe kerf 9, the lower portion of the cup not expanding; This'will -continue until the upper portion of the cup has been worn away sufliciently, andwhen this point has been reached a newcup v7 may be supplied.

Th-e housing 18 will serve to prevent iiuid and sand fromrcoming incont'act with the springl5,iand will thus assure the constant and accurate working of the expanding means. As will be obvious,.my expanding cup may `be cheaply made and will wear for` long periods before it is necessary to renew the cup,land when a renewal is necessary the .-cup maybe quickly removed and replaced without the loss of time and expense.

.Having thus described my invention, what I claim as new'and desire to protect by Let- Y ters. Patent is:

l. In a pump plunger, an expanding cup comprisingia frusto-conical tubular member longitudinally' divided on` planes tangent to the inner face thereof, a cup-shaped washer ,'.to retain said sections together, a recessed .upperr face `on said cup, a. conical expanding member fitting therein, and resilient means vbearing on said expanding member to Vautomatically expand said cupV during the operation of the plunger.

2. In a pump plunger a tubular member, an expanding cup thereon comprising a frusto-conical member slidable upon said tubular member, a cup shaped washer fitting about the lower portion of said cup, said cup having an annular kerf on the inner face thereof, and means to force said expanding cup outwardly in the manner described.

3. In a pump plunger a tubular member, a cup shaped washer thereon, an expanding cup fitting within said washer and having an inner kerf below the upper endof said washer, said cup being longitudinally divided into a plurality of parts on planes tangent with the inner face thereof, a conical expanding member tting within the upper end of said cup and resilient means forcing said expanding means into contact with said cup.

4;. In a pump plunger atubular member, a cup shaped washer thereon, a frusto-coni cal expanding cup seated in said washer, said cup being divided longitudinally into a plurality of sections, a beveled recess on the upper face of said cup, a sharp outer edge on said upper face, an expanding means fitting within said recess, a spring bearing upon said expanding means and adapted to force the same downwardly in the manner described, and means to protect Said spring from sand.

5. In a pump plunger a tubular member, an expanding cup secured thereon, an expanding means bearing against the upper face of said cup, a spring bearing against said expanding means and tending to force the same downwardly against said cup, and a housing for said spring slidable upon said plunger.

6. In a pump plunger a tubular member, a longitudinally divided cup thereon, means to expand one end of said cup independently of the other, means to retain the non-ex panding end in position, all that part of said cup above said retaining means being adapted to expand simultaneously.

In a pump plunger, a frusto-conical shaped cup longitudinally divided along planes tangent to the inner face thereof, a cup shaped washer fitting over the smaller end thereof, an annular kerf cut on the said inner face adjacent the upper end of said washer and means to force the larger end of said cup outwardly in the manner described.

In testimony whereof, I hereunto aiix my signature this the 10th day of July, A. D. 1920.

ROBERT E. CARMICHAEL. 

